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<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>函数参数默认值</title>
</head>

<body>
    <script>
        //ES6 允许给函数参数赋值初始化
        //1. 形参初始值 具有默认值的参数, 一般位置要靠后
        function add(a, b, c = 10) {
            return a + b + c;
        }
        let res = add(1, 2);
        console.log(res);

        //2. 与解构赋值结合
        // function connect(options) {
        //     let { host, username, password, port } = options;

        // }
        function connect({ host = '127.0.0.1', username, password, port }) {
            console.log({ host, username, password, port });
        }
        connect({
            // host: 'localhost',
            username: 'root',
            password: 'root',
            port: 3306,
        });

    </script>
</body>

</html>